Air pollution causes more heart attacks than cocaine, and is as threatening a trigger as coffee, alcohol, and physical exertion, researchers find. They combined data from 36 individual studies in order to calculate each cause's population-attributable fraction, or PAF—basically, the proportion of all heart attacks attributed to each trigger. No. 1? Exposure to traffic, and the air pollution that comes with it. Following that, in descending order: physical exertion, alcohol, coffee, air pollution, and then triggers like anger, sex, cocaine use.
“Of the triggers for heart attack studied, cocaine is the most likely to trigger an event in an individual, but traffic has the greatest population effect as more people are exposed to (it),” researchers said. “Physicians are always looking at individual patients—and low risk factors might not look important at an individual level, but if they are prevalent in the population then they have a greater public health relevance,” adds a scientist. The study suggests doctors should consider wider threats to heart health more closely alongside individual risks, such as drug use—which may be higher but are also rarer, Reuters reports. (Read more air pollution stories.)